Walnut black spot is very common, is there any way to prevent walnut black spot?

It is necessary to apply some ointment to its trunk and branches after falling leaves, which can have the effect of heat preservation and frost prevention, and can spray pesticides on his tree, which can be wrapped in a protective film, and can also enhance the efficacy, so as to effectively prevent rainwater pollution.

It is necessary to prevent before germination, maintain the drainage performance of the soil, and spray the disease if it is found, which can be protected with streptomycin and some Bordeaux liquid.

If the disease has been on, then it is necessary to spray pesticides in time and reconcile them according to a certain proportion, so that they can be effectively prevented.

The method of prevention and control is to first choose disease-resistant walnut varieties to plant, and then cover the greenhouse with mulch, maintain temperature, spray pesticides regularly, and prevent the emergence of this disease on the rhizomes and leaves of walnuts.

Walnut black spot is very common, is there any way to prevent walnut black spot?

Walnut black spot disease is a common bacterial disease in the process of walnut seeds, which not only harms the leaves and new leaves of walnut, but also harms the bud inflorescence and fruit of walnut, which is very harmful to the fruit, resulting in a large area of black rot falling off of walnut fruit trees, being inedible or losing their commercial value. Let's talk about it today, what to do about walnut black spot disease? Symptoms and prevention methods of walnut black spot Symptoms of walnut black spot disease Fruit lesions are small black-brown spots at first, and then expand into round or irregular black spots.

There are no obvious edges, and there is a water-stained halo around it. At the onset of the disease, the lesions** sag, cracked and turned grayish-white, and the fruit was slightly deformed. When the damage is severe, it will cause the whole fruit to quickly turn black and rot, and fall early.

When the young fruit is diseased, because the endocarp has not hardened, the pathogen expands inward and causes the kernel to rot. When the fruit is close to maturity, the disease is limited to the exocarp due to the gradual hardening of the kernel shell, and the damage is relatively light. The lesions on the leaves first appear small black spots along the veins, and then expand into nearly round or polygonal black-brown lesions, with translucent halos on the outer edges, mostly water-stained.

In the later stage, the lesion** is gray or perforated, and in severe cases, the whole leaf is black, brittle, and incomplete. The lesions on the petioles and young tips are oblong or irregularly shaped, black-brown, slightly concave, and the lesions surround the branches.

Summary. Prevention and control methods of walnut black spot disease:

1. Strengthen cultivation management, combined with pruning, remove diseased fruits, branches and leaves in time, strengthen ventilation and light transmission, and improve the structure of the tree.

2. Spray 1 time of 3-5 Baumé stone sulfur mixture before germination to eliminate overwintering bacteria. Spray 1-3 times during the growth period: 200 Bordeaux solution, or 500-800 times of methyl tobuzin or antibacterial special wettable powder (1 time before female flowering, 1 time after flowering and 1 time at young fruit stage); You can also use 50 mg of streptomycin plus 2% copper sulfate and spray it once in 15 days, and the effect is good.

Walnut black spot is very common, is there any way to prevent walnut black spot?

Prevention and control methods of walnut black spot disease: 1. Strengthen cultivation management, combined with pruning, remove diseased fruits, diseased branches and diseased leaves in time, strengthen ventilation and light transmission, and improve the structure of the tree. 2. Spray 1 time of 3-5 Baumé stone sulfur mixture before germination to eliminate overwintering bacteria.

Spray 1-3 times during the growth period: 200 Bordeaux solution, or 500-800 times of methyl tobuzin or antibacterial special wettable powder (1 time before female flowering, 1 time after flowering and 1 time at young fruit stage); You can also use 50 mg of streptomycin plus 2% copper sulfate and spray it once in 15 days, and the effect is good.

Walnut black spot disease occurs mainly in early summer, when there is a lot of rain, and can last until early autumn. This disease will seriously endanger the growth of plants, and it is necessary to spray and treat it in time when it is found. Drugs can be streptomycin, uninmycin, chunleimycin, etc.

After one week of medication, it is protected by Bordeaux liquid, copper pineinate, basic copper sulfate, etc. In addition, it is necessary to take precautions in time before budding in spring. <>

The above are the key points of the prevention and control technology of walnut black spot <>

Walnut black spot is very common, is there any way to prevent walnut black spot?

Walnut black spot is very common, is there any way to prevent walnut black spot? Walnut is a very important economic fruit tree, now widely planted by farmers, but when planting walnuts, walnuts are prone to a variety of pests and diseases, resulting in walnut yield reduction or plant death, so farmers should pay attention to pest control, to improve the economic benefits of walnuts, and then understand the symptoms and prevention methods of walnut black spot disease! First, the symptoms of walnut black spot disease The disease mainly harms leaves, new shoots and fruits, after the onset of leaves, there will be round or polygonal small brown spots in the leaf veins, and the later lesions become larger, and translucent halos appear, serious is the whole leaf blackening, after the onset of the branch, there will be brown elongated lesions, and in severe cases, the lesions will die due to the expansion of the lesions around the branches.

After the onset of the fruit, there will be brown soft spots, and around the appearance of water-stained halos, when the harm is serious, the fruit quickly turns black and rots, early fruit drop, young fruit disease will also cause kernel rot, the old fruit harm is relatively light. 2. Walnut black spot disease prevention and control method 1, breeding resistant varieties When breeding walnut varieties, we should choose varieties with strong disease resistance, which is very helpful to enhance the potential and disease resistance of walnut trees. 2. Strengthen management, in the process of planting walnuts, we should pay attention to reasonable fertilization, improve the growth rate of walnuts, timely remove long branches and over-dense branches, reduce planting density, improve the light transmission environment, and improve disease resistance.

3. Do a good job of clearing the garden, after harvesting and falling leaves, it is necessary to clean the fallen leaves, weeds, rotten fruits, and diseased fruits in the orchard in a timely manner, and take them away from the orchard to clean up, combine pruning, cut off diseased and insect branches and dry branches, and reduce the harm of the source of disease. 4. Chemical control, once walnut black spot disease occurs, it is necessary to use Bordeaux liquid spraying 200 times the liquid for spraying, spraying every 7-10 days, which can play a good prevention and control effect, and the control effect of streptomycin or streptomycin plus 2% copper sulfate is also very good. The above is all the introduction to the prevention and control methods of walnut black spot, if farmers want to plant high-yield walnuts, they must master the scientific pest control technology, I hope this article will help you.

Summary. Walnut black spot disease is a walnut disease that many walnut growers have encountered, mainly harming leaves, shoots, fruits and male flowers, and is a worldwide disease.

Walnut black spot is very common, is there any way to prevent walnut black spot?

Walnut black spot disease is a walnut disease that many walnut growers have encountered, mainly harming leaves, shoots, fruits and male flowers, and is a worldwide disease.

Prevention and control methods of walnut black spot disease 1, after clearing the garden to make a tremble, clean up the branches and leaves and diseased fruits in time and take them out of the orchard, bury them deep or burn them. 2. Cultivate and cultivate disease-resistant varieties to maintain the healthy growth of the tree and enhance disease resistance. 3. Timely remove long branches, overly dense branches, diseased and insect branches, reduce the density of orchards, and improve the ventilation and light transmission conditions in the orchard and canopy.

4. Pharmaceutical prevention and control, spray Baume 3 5 degrees stone sulfur mixture before germination. Spray 1:2 from May to June

200 times Bordeaux liquid or 50% methyl tobuzin wettable powder 500-800 times solution, spray once before female flowers bloom, after blooming and at the young fruit stage.

Walnut black spot disease occurs on leaves, twigs, flowers and fruits. After leaf damage, small brown spots that are nearly round and polygonal first appear on the veins. In severe cases, they can heal each other.

The leaves appear perforated in the later stage, the lesions on the petiole are long brown and slightly sunken, the diseased leaves are shrunken and deformed, and when the trees enter the growth period, they also need to spray 1:05:200 times of Bordeaux liquid, of course, the effect of spraying copper oxalate is also very good, you can also use the concentration of agricultural streptomycin plus 2 copper sulfate, spray once every half a month, spray multiple times, you can also achieve good results.

The dry rot of walnut trees mainly harms its branches, and pathogenic pathogens will infect young branches and trunks, and in the early stage of the disease, brown round lesions will appear on the branches or branches, and the lesions are slightly raised, and the juice can flow out by pressing. With the aggravation of the disease, the lesions on the branches will gradually increase and expand, parathion microcapsules or 25% phosphine microcapsules, according to 250 grams per mu, mixed with 25 50 kg of water, evenly and carefully sprayed. Before spraying, the ground weeds should be removed, and it is best to plow the ground soil after spraying to prolong the effect, and the second treatment should be carried out according to the same method after 20 days.

Because walnut tree rot disease causes the external cortex to decay and drain black water, it is also called "black water disease". The rot disease of walnut tree is a fungal disease caused by the fungus of the subphylum Semi-Knowitives, which mainly harms the main side branches of the tree, and begins to rot from the subphloem layer of the diseased part, mostly in the form of water stains, and the later lesions are gray or perforated, and the whole leaf is black, brittle, and incomplete when it is severe. The lesions on the petioles and young shoots are round or irregularly shaped, black-brown and slightly concave, and the lesions surround the branches, causing dead shoots and leaf drop.

Virus control. For diseased trees, it is necessary to spray the whole garden in time with a new high-fat film to form a protective film to enhance the efficacy, and use ulcer to spray the whole garden to kill germs and nourish the tree. Prevent and control germs to spread through wind and rain.

In severe cases, the upper segment dies due to the expansion of the lesion and the protective branches. When the young fruit is damaged, small black spots appear on the fruit surface, without obvious edges, and then gradually expand into pieces and turn black, and penetrate deep into the pulp, so that the whole fruit and the kernel all turn black and rot and fall off. After the inflorescence is invaded, it produces black-brown water-stained lesions.

It is necessary to choose disease-resistant varieties, and at the same time to turn over the soil, do a good job of weeding, and at the same time clean up all the diseased fruits and leaves in the orchard, and at the same time use more nutritious fertilizers, do more pruning work, and use professional agents, so that walnuts will not appear black spot disease.

Usually pay attention to pruning, you can also use pesticides to prevent and control, regular fertilization, and clear the garden in winter, in fact, the dead branches and fallen leaves and pests on the ground caused by fruit drop in time to clean up.

You can often prune branches and leaves, fertilize, so that you can also enhance the ability to resist disease, you can also use the method of pesticide control, spray some insect repellents, so that you can control it well.

During the planting process, it is necessary to pay attention to the surrounding environment, maintain the temperature and humidity of the soil, and pay attention to the time of watering.

1. Spraying agent: use streptomycin and uninmycin for spraying. 2. Prune the leaves

Cut off all the branches and leaves infected with the disease and burn them. 3. Keep ventilation: provide a ventilated and breathable growth environment for walnuts, and cut the dense leaves.

4. Reasonable water and fertilizer: apply compound fertilizer rich in nutrients frequently, improve disease resistance, and reduce watering.

1. Spray the agent

Walnut tree black spot disease mainly occurs at the beginning of summer, when there is a lot of rain is the most serious, after the discovery should be sprayed in time to treat, the drug can be streptomycin, uninmycin, etc., and the walnut should be sprayed once every 1 week.

2. Prune the leaves

After the walnut tree is infected with black spot disease, the diseased branches and leaves should be pruned to prevent the spread of the disease, and then the cut branches and leaves are stacked in an open place and burned.

3. Keep ventilation

Good ventilation is essential for walnut tree growth, and during the plant growth period, the dense leaves can be cut off to improve ventilation between the canopies, and when the weather is hot, the walnut tree can be blown with an electric fan.

4. Reasonable water and fertilizer

In the process of breeding walnut trees, it is necessary to apply sufficient fertilizer to it, which is conducive to improving the disease resistance of the plant, mainly based on compound fertilizer rich in nutrients, and in the rainy season, it is necessary to reduce the watering of walnut trees, and to discharge the water in the soil.

[Harmful characteristics]: Walnut black spot disease symptoms Walnut black spot disease is also known as black rot. It is mainly harmful to young fruits and leaves, and can also be harmful to young branches.

The young fruit is infected, and the fruit surface has small brown spots, the edge is not obvious, and then it turns black and deep to the pulp, causing the whole walnut and kernel to turn black or rot and fall off. After the near-ripe fruit is infected, it is first confined to the exocarp, and then spreads to the mesocarp, causing the diseased part of the peel to fall off, the endocarp is exposed, and the kernel is intact. Leaf infection, first on the leaf veins appear nearly round or polygonal small brown spots, expand and heal with each other, the periphery of the lesion is water-stained halo, a few perforations in the later stage, the diseased leaves shrink and deform.

Pathogen]: Xanthomonas Campestris Pierce Dye Synonyms: Xanthomonas Juglandis (Pierce) Dowson...

Called Xanthomonas genus, the brillaria nigra rot xanthomonas walnut black spot to the disease type, is a bacterium. The thallus is short rod-shaped, microns in size, terminal 1 flagella, cultivated in the blue sky line of the bevel plane of beef juice glucose agar, the colony is protruding, the growth is vigorous, smooth and opaque with luster, light lemon yellow, sticky, the growth temperature is 28 32, the highest is 37, the lowest is 5, 53 55 10 minutes lethal, adaptation, pH 6 8 is optimal.

Pathogenesis ]: Pathogenic bacteria overwinter in branches or buds. In the following spring, the bacterial fluid is transmitted by wind and rain, and invades from stomata, skin pores, nectar glands and wounds, causing infection of leaves, fruits or shoots.

Under 4 30 conditions, the host epidermis is moist and pathogens can invade leaves or fruits. The incubation period is 5 to 34 days, and in the field it is mostly 10 to 15 days. Walnut flower stage and susceptible to disease, rainy summer disease is serious.

Wounds caused by walnut limb moths are susceptible to infection by the fungus.

Control methods] :(1) timely control of walnut pests. (2) Spraying 4000 times of Bordeaux solution or 72% agricultural streptomycin soluble powder and 400,000 units of penicillin potassium salt are also effective for diluting water into 5000 times when walnut leaves are spreading and after flowering.